US2684517A - Concrete pipe casting apparatus - Google Patents

Concrete pipe casting apparatus Download PDF

Info

Publication number
US2684517A
US2684517A US253846A US25384651A US2684517A US 2684517 A US2684517 A US 2684517A US 253846 A US253846 A US 253846A US 25384651 A US25384651 A US 25384651A US 2684517 A US2684517 A US 2684517A
Authority
US
United States
Prior art keywords
tube
jacket
core
hooks
casting
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US253846A
Inventor
Randell C Woods
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to US253846A priority Critical patent/US2684517A/en
Application granted granted Critical
Publication of US2684517A publication Critical patent/US2684517A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B28WORKING CEMENT, CLAY, OR STONE
    • B28BSHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
    • B28B21/00Methods or machines specially adapted for the production of tubular articles
    • B28B21/76Moulds
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S425/00Plastic article or earthenware shaping or treating: apparatus
    • Y10S425/117Pallet

Definitions

  • This invention relates to concrete pipe casting apparatus and more particularly to an outer mould or jacket in which concrete pipe sections are cast.
  • an outer mould or jacket for casting concrete pipe sections which jacket is of substantially unitary construction and is not circumferentially expansible to release a cast pipe section therefrom, which includes a unitary, substantially cylindrical shell having no longitudinal cut or opening for expanding the shell and can thus have materially less weight and greater strength than equivalent mould jackets having longitudinal cuts or openings therein for circumferential expansion thereof; which is slightly tapered from end to end to provide suflicient draft for facilitating removal of the jacket longitudinally from a pipe section cast therein and has handles or lugs projecting therefrom for also facilitating removal of the jacket from the pipe section; which is releasably connectible at its larger end to a pallet ring and includes quick release means for freeing it from the pallet ring; and which is simple and durable in construction, economical to manufacture, and adaptable for use with various types of concrete tamping and packing machines.
  • Figure l is a top plan view of a mould jacket illustrative of the invention shown in operative association with a pallet ring and a portion of a concrete tamping machine;
  • Figure 2 is a side elevational view of the assembly illustrated in Figure l, a portion of the jacket being broken away and shown in longitudinal cross section to better illustrate the construction thereof;
  • Figure 3 is a side elevational View of the assembly rotated 90 from the position illustrated in Figure 2.
  • the numeral I Il designates a cylindrical inner form or core for moulding concrete pipe sections, this core constituting a portion of a concrete tamping machine of a form well known to the art and being mounted at one end on a plate II which also constitutes a part of the tamping machine.
  • the core I@ is slightly tapered in a direction away from the base plate I I to provide draft for facilitating the removal of the core from a concrete pipe section cast thereon.
  • An annular pallet ring I2 is shown supported on the base plate II and surrounding the core lil adjacent the base plate.
  • the pallet ring is also of well known construction, the form illustrated being a form provided to produce tongue formations on the ends of pipe sections for joining pipe sections together in end to end relationship.
  • the pallet rings are made in various other shapes for different purposes and are removable with the casting from the core I0 when the casting is removed from the core, these pallet rings being left in place on the casting until the casting has completely set.
  • the pallet ring is supported in position on the base plate I I by suitable supporting blocks I3 and other blocks Iii are provided on the base plate and project upwardly therefrom for centering an outer mould casing or jacket on the base plate so that it surrounds the core I6 and is annularly spaced from the core a uniform distance entirely around the latter.
  • the base plate with the mounting and centering blocks and the pallet ring are all well known to the art and constitute no part of the present invention except in the association thereof with the novel mould jacket, a further illustration and description of these elements is considered unnecessary for the purposes of the present disclosure.
  • rlhe outer mould casing or jacket of the present invention is generally indicated at I5 and comprises a metal tube It of cylindrical shape having a length substantially equal to the length of the core I0 and an inside diameter greater than the outside diameter of the core by twice the wall thickness of the concrete pipe section to be cast between the core and the jacket.
  • the tube I6 is preferably formed of a durable material, such as hardened aluminum, and has smooth inner and outer surfaces and is slightly tapered from one end to the other to provide draft for facilitating the removal of the jacket from a concrete pipe section cast therein.
  • a reinforcing band Il surrounds the tube I6 at the smaller end of the latter and has an inwardly directed annular flange I 8 at one end overlying the adjacent smaller end of the tube, this being the upper end of the tube when the tube is disposed in operative association with the core I0, as is particularly illustrated in Figure 2.
  • a reinforcing band It Wider than the band I'I surrounds the larger, bottom end of the tube and reinforcing bands 20 and 2
  • Plates 22 and 23 are secured to the outer surface of the tube l@ substantially at the midlength location of the tube and at diametrically opposed locations therearound with their upper ends adjacent the bottom edge of the reinforcing ing 2i) and lugs or handles 2d and 25 project outwardly one from each of these plates substantially radially of the tube l. in the case of small jackets these handles may be grasped. by a hand to facilitate removing the jackets from concrete pipe sections cast therein and in the case of larger jackets these handles or lugs may be engaged by a hoist chain or cable for removing the jackets from the cast pipe sections.
  • Apertured lugs project outwardly from the tube it at substantially diametrically opposite locations around the tube and near the larger end of the tube, these lugs being disposed adjacent the upper edge of the bottom reinforcing band i9, as is clearly illustrated in ' Figures 2 and 3.
  • Hooks 23 and 29 are pivotally connected intermediate their lengths to the lugs 2t and El, respectively, and extend longitudinally of the tube l5.
  • the lugs are preferably provided in pairs of spaced apart lugs and each hook is disposed between the lugs of one pair, the lugs of each pair having registering apertures therein, and pivot pins Sli and 3i extend through the apertured lugs and through registering apertures in the hooks 28 and 2d respectively to pivotaily connect the hooks to the tube i5 for movement about aXes which are slightly spaced from but are generally tangent to the outer surface of the tube.
  • the hooks are provided with notches, as indicated at 32, for the hook 2S, which notches provide hooks formations at these ends of the hooks engageable with the rim of the pallet ring I2 to releasably lock the pallet ring to the tube l at the larger, lower end of the latter.
  • Compression springs 32 and 34 are disposed between the tube i6 and the ends of the hooks 23 and 2? respectively, remote from the hook formations thereon and these springs resiliently urge the hook formations of the hooks inwardly of the tube and into locking engagement with the rim of the pallet ring i2.
  • the bottom reinforcing ring i9 and the tube are provided with apertures, as indicated at 34, through which the ends of the hooks having the hook formations extend and reinforcing plates 3E and 3S are mounted on the outer surface of the tube and interposed between the tube and the adjacent ends of the spring 32'. and 33.
  • a bail 3l extends between the hooks 23 and 29 and the tube i5 at the under side of the lugs 2S and 27 and is pivotally secured at its ends to the bottom reinforcing ring I9, as indicated at 33 and 39, for rocking movement about axes disposed substantially radially of the tube and including an angle of approximately 90 therebetween.
  • This bail bears against the inner edges of the hooks between the lugs 28 and 2i' and the lower ends of the hooks, the inner edge portions of the hooks at the location thereof engaged by the bail being curved inwardly of the tube, as is particularly illustrated in Figure 2.
  • the pallet ring is rst assembled with the core l@ and base plate l l and supported on the blocks i3 surrounding the bottom end of the core.
  • the jacket i5 is then assembled with core and the pallet ring so that the pallet ring is received in the lower, larger end of the jacket and the jacket is uniformly spaced from the core.
  • the concrete to form the pipe section is then packed or tamped into the annular Space between the core and the jacket by a suitable mechanism well known to the art, the hooks 28 and 25B at this time engaging the rim of the pallet ring to lock the jacket and pallet ring together.
  • the core is withdrawn leaving the jacket and pallet ring locked together and in piace on the casting.
  • the casting with the pallet ring and jacket is then moved to the curing room and the jacket is then lifted off of the casting after first releasing the hooks from the pallet ring, in the manner indicated above.
  • the casting is then left standing on the pallet ring until a predetev mined cure of the concrete casting has been obtained at which time the pallet ring is removed and returned to use with the packing or tamping machine.
  • the jacket assembly of the present invention is of minimum weight and maximum strength because of its unitary construction and that it can be easily removed from the casting upon freeing it from the pilot ring at the bottom of the casting.
  • a jacket assembly for casting concrete pipe sections comprising a metal tube of cylindrical shape, reinforcing bands surrounding said tube one at each end thereof, outwardly projecting handles secured to said tube intermediate the length thereof, and manually operable means carried by said tube at one end thereof for releasably locking a pallet ring in said one end of the tube, said tube being slightly tapered from said one to the other end thereof to provide draft for facilitating longitudinal separation of said tube from a concrete pipe section cast therein, and said manually operable means including hooks pivotally mounted on said tube near said one end of the latter and extending through apertures in said tube and the adjacent reinforcing band to engage the rim of a pallet ring disposed within said one end of the tube, springs interposed between said tube and said hooks resiliently urging the latter in a pallet ring engaging direction, and a foot operated element pivotally mounted on said tube and engaging said hooks to move the latter in a pallet ring releasing direction when said foot operated element is depressed by foot pressure thereon.
  • a jacket assembly for casting concrete pipe sections comprising a tube of substantially cylindrical shape adapted to be disposed in upright position, a core disposed in said tube and extending longitudinally thereof in circumferentially spaced relationship thereto, a pallet ring disposed in the lower end of said tube in surrounding relationship to the adjacent end of said core, and manual operable means carried by said tube at a lower end thereof for releasably locking said pallet ring in said lower end of the tube, said manually operable ⁇ means including hooks pivotally mounted on said tube near the lower end of the latter and extending through apertures in said tube to engage the rim of said pallet ring, springs interposed between said tube and said hooks resiliently urging the latter into the pallet References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 32,754 Chilver July 9, 1861 862,123 Adams Aug. 6, 1907

Landscapes

  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Ceramic Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing Of Tubular Articles Or Embedded Moulded Articles (AREA)

Description

July 27, 1954 R. c. wooDs CONCRETE PIPE CASTING APPARATUS Filed Oct. 30, 1951 l nl INVENTOR 9a/mm ATToRNEY Patented July 27, 1954 UNITED STATES PATENT GFFICE 2 Claims.
This invention relates to concrete pipe casting apparatus and more particularly to an outer mould or jacket in which concrete pipe sections are cast.
it is among the objects of the invention to provide an outer mould or jacket for casting concrete pipe sections which jacket is of substantially unitary construction and is not circumferentially expansible to release a cast pipe section therefrom, which includes a unitary, substantially cylindrical shell having no longitudinal cut or opening for expanding the shell and can thus have materially less weight and greater strength than equivalent mould jackets having longitudinal cuts or openings therein for circumferential expansion thereof; which is slightly tapered from end to end to provide suflicient draft for facilitating removal of the jacket longitudinally from a pipe section cast therein and has handles or lugs projecting therefrom for also facilitating removal of the jacket from the pipe section; which is releasably connectible at its larger end to a pallet ring and includes quick release means for freeing it from the pallet ring; and which is simple and durable in construction, economical to manufacture, and adaptable for use with various types of concrete tamping and packing machines.
Other objects and advantages will become apparent from a consideration of the following desoription and the appended claims in conjunction with the accompanying drawings, wherein:
Figure l is a top plan view of a mould jacket illustrative of the invention shown in operative association with a pallet ring and a portion of a concrete tamping machine;
Figure 2 is a side elevational view of the assembly illustrated in Figure l, a portion of the jacket being broken away and shown in longitudinal cross section to better illustrate the construction thereof; and
Figure 3 is a side elevational View of the assembly rotated 90 from the position illustrated in Figure 2.
With continued reference to the drawings, the numeral I Il designates a cylindrical inner form or core for moulding concrete pipe sections, this core constituting a portion of a concrete tamping machine of a form well known to the art and being mounted at one end on a plate II which also constitutes a part of the tamping machine. The core I@ is slightly tapered in a direction away from the base plate I I to provide draft for facilitating the removal of the core from a concrete pipe section cast thereon.
An annular pallet ring I2 is shown supported on the base plate II and surrounding the core lil adjacent the base plate. The pallet ring is also of well known construction, the form illustrated being a form provided to produce tongue formations on the ends of pipe sections for joining pipe sections together in end to end relationship. The pallet rings are made in various other shapes for different purposes and are removable with the casting from the core I0 when the casting is removed from the core, these pallet rings being left in place on the casting until the casting has completely set.
The pallet ring is supported in position on the base plate I I by suitable supporting blocks I3 and other blocks Iii are provided on the base plate and project upwardly therefrom for centering an outer mould casing or jacket on the base plate so that it surrounds the core I6 and is annularly spaced from the core a uniform distance entirely around the latter.
As the core, the base plate with the mounting and centering blocks and the pallet ring are all well known to the art and constitute no part of the present invention except in the association thereof with the novel mould jacket, a further illustration and description of these elements is considered unnecessary for the purposes of the present disclosure.
rlhe outer mould casing or jacket of the present invention is generally indicated at I5 and comprises a metal tube It of cylindrical shape having a length substantially equal to the length of the core I0 and an inside diameter greater than the outside diameter of the core by twice the wall thickness of the concrete pipe section to be cast between the core and the jacket. The tube I6 is preferably formed of a durable material, such as hardened aluminum, and has smooth inner and outer surfaces and is slightly tapered from one end to the other to provide draft for facilitating the removal of the jacket from a concrete pipe section cast therein.
A reinforcing band Il surrounds the tube I6 at the smaller end of the latter and has an inwardly directed annular flange I 8 at one end overlying the adjacent smaller end of the tube, this being the upper end of the tube when the tube is disposed in operative association with the core I0, as is particularly illustrated in Figure 2.
A reinforcing band It, Wider than the band I'I surrounds the larger, bottom end of the tube and reinforcing bands 20 and 2| surround the tube at spaced apart locations between the end bands I'I and I9.
Plates 22 and 23 are secured to the outer surface of the tube l@ substantially at the midlength location of the tube and at diametrically opposed locations therearound with their upper ends adjacent the bottom edge of the reinforcing ing 2i) and lugs or handles 2d and 25 project outwardly one from each of these plates substantially radially of the tube l. in the case of small jackets these handles may be grasped. by a hand to facilitate removing the jackets from concrete pipe sections cast therein and in the case of larger jackets these handles or lugs may be engaged by a hoist chain or cable for removing the jackets from the cast pipe sections.
Apertured lugs, as indicated at 2E and 2l' project outwardly from the tube it at substantially diametrically opposite locations around the tube and near the larger end of the tube, these lugs being disposed adjacent the upper edge of the bottom reinforcing band i9, as is clearly illustrated in 'Figures 2 and 3.
Hooks 23 and 29 are pivotally connected intermediate their lengths to the lugs 2t and El, respectively, and extend longitudinally of the tube l5. The lugs are preferably provided in pairs of spaced apart lugs and each hook is disposed between the lugs of one pair, the lugs of each pair having registering apertures therein, and pivot pins Sli and 3i extend through the apertured lugs and through registering apertures in the hooks 28 and 2d respectively to pivotaily connect the hooks to the tube i5 for movement about aXes which are slightly spaced from but are generally tangent to the outer surface of the tube.
At their ends adjacent the larger or lower end of the tube the hooks are provided with notches, as indicated at 32, for the hook 2S, which notches provide hooks formations at these ends of the hooks engageable with the rim of the pallet ring I2 to releasably lock the pallet ring to the tube l at the larger, lower end of the latter.
Compression springs 32 and 34 are disposed between the tube i6 and the ends of the hooks 23 and 2? respectively, remote from the hook formations thereon and these springs resiliently urge the hook formations of the hooks inwardly of the tube and into locking engagement with the rim of the pallet ring i2. The bottom reinforcing ring i9 and the tube are provided with apertures, as indicated at 34, through which the ends of the hooks having the hook formations extend and reinforcing plates 3E and 3S are mounted on the outer surface of the tube and interposed between the tube and the adjacent ends of the spring 32'. and 33.
A bail 3l extends between the hooks 23 and 29 and the tube i5 at the under side of the lugs 2S and 27 and is pivotally secured at its ends to the bottom reinforcing ring I9, as indicated at 33 and 39, for rocking movement about axes disposed substantially radially of the tube and including an angle of approximately 90 therebetween. This bail bears against the inner edges of the hooks between the lugs 28 and 2i' and the lower ends of the hooks, the inner edge portions of the hooks at the location thereof engaged by the bail being curved inwardly of the tube, as is particularly illustrated in Figure 2. With this arrangement, when the free intermediate portion of the bail is forced downwardly as by foot pressure of the operator, the ends of the hooks engaging the pallet ring i2 are forced outwardly against the force of springs 32 and 35 to release the pallet ring from the outer mould jacket so 4 that the outer jacket can be lifted off of the pipe section casting therein.
In using the apparatus, the pallet ring is rst assembled with the core l@ and base plate l l and supported on the blocks i3 surrounding the bottom end of the core. The jacket i5 is then assembled with core and the pallet ring so that the pallet ring is received in the lower, larger end of the jacket and the jacket is uniformly spaced from the core. The concrete to form the pipe section is then packed or tamped into the annular Space between the core and the jacket by a suitable mechanism well known to the art, the hooks 28 and 25B at this time engaging the rim of the pallet ring to lock the jacket and pallet ring together. As soon as the casting has hardened suiciently the core is withdrawn leaving the jacket and pallet ring locked together and in piace on the casting. The casting with the pallet ring and jacket is then moved to the curing room and the jacket is then lifted off of the casting after first releasing the hooks from the pallet ring, in the manner indicated above. The casting is then left standing on the pallet ring until a predetev mined cure of the concrete casting has been obtained at which time the pallet ring is removed and returned to use with the packing or tamping machine.
It will be noted that the jacket assembly of the present invention is of minimum weight and maximum strength because of its unitary construction and that it can be easily removed from the casting upon freeing it from the pilot ring at the bottom of the casting.
The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are, therefore, intended to be embraced therein.
What is claimed is:
1. A jacket assembly for casting concrete pipe sections comprising a metal tube of cylindrical shape, reinforcing bands surrounding said tube one at each end thereof, outwardly projecting handles secured to said tube intermediate the length thereof, and manually operable means carried by said tube at one end thereof for releasably locking a pallet ring in said one end of the tube, said tube being slightly tapered from said one to the other end thereof to provide draft for facilitating longitudinal separation of said tube from a concrete pipe section cast therein, and said manually operable means including hooks pivotally mounted on said tube near said one end of the latter and extending through apertures in said tube and the adjacent reinforcing band to engage the rim of a pallet ring disposed within said one end of the tube, springs interposed between said tube and said hooks resiliently urging the latter in a pallet ring engaging direction, and a foot operated element pivotally mounted on said tube and engaging said hooks to move the latter in a pallet ring releasing direction when said foot operated element is depressed by foot pressure thereon.
2. A jacket assembly for casting concrete pipe sections comprising a tube of substantially cylindrical shape adapted to be disposed in upright position, a core disposed in said tube and extending longitudinally thereof in circumferentially spaced relationship thereto, a pallet ring disposed in the lower end of said tube in surrounding relationship to the adjacent end of said core, and manual operable means carried by said tube at a lower end thereof for releasably locking said pallet ring in said lower end of the tube, said manually operable` means including hooks pivotally mounted on said tube near the lower end of the latter and extending through apertures in said tube to engage the rim of said pallet ring, springs interposed between said tube and said hooks resiliently urging the latter into the pallet References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 32,754 Chilver July 9, 1861 862,123 Adams Aug. 6, 1907
US253846A 1951-10-30 1951-10-30 Concrete pipe casting apparatus Expired - Lifetime US2684517A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US253846A US2684517A (en) 1951-10-30 1951-10-30 Concrete pipe casting apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US253846A US2684517A (en) 1951-10-30 1951-10-30 Concrete pipe casting apparatus

Publications (1)

Publication Number Publication Date
US2684517A true US2684517A (en) 1954-07-27

Family

ID=22961947

Family Applications (1)

Application Number Title Priority Date Filing Date
US253846A Expired - Lifetime US2684517A (en) 1951-10-30 1951-10-30 Concrete pipe casting apparatus

Country Status (1)

Country Link
US (1) US2684517A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2814848A (en) * 1955-01-10 1957-12-03 Charles B Pausch Locking mechanism for a pipe mold structure
US3183572A (en) * 1963-09-23 1965-05-18 Fresno Valves Inc Holder for pipe forming device
US3530553A (en) * 1967-03-17 1970-09-29 Thomas J Engle Concrete pipe bell depression former
FR2093910A1 (en) * 1969-05-20 1972-02-04 Daulouede Et Duvicq
US4134568A (en) * 1977-04-07 1979-01-16 Hydrotile Canada Limited Plural molds with common actuating means

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US32754A (en) * 1861-07-09 Improvement in molds for molding pipes of plastic materials
US862123A (en) * 1906-12-06 1907-08-06 Edward L Adams Pipe-mold.

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US32754A (en) * 1861-07-09 Improvement in molds for molding pipes of plastic materials
US862123A (en) * 1906-12-06 1907-08-06 Edward L Adams Pipe-mold.

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2814848A (en) * 1955-01-10 1957-12-03 Charles B Pausch Locking mechanism for a pipe mold structure
US3183572A (en) * 1963-09-23 1965-05-18 Fresno Valves Inc Holder for pipe forming device
US3530553A (en) * 1967-03-17 1970-09-29 Thomas J Engle Concrete pipe bell depression former
FR2093910A1 (en) * 1969-05-20 1972-02-04 Daulouede Et Duvicq
US4134568A (en) * 1977-04-07 1979-01-16 Hydrotile Canada Limited Plural molds with common actuating means

Similar Documents

Publication Publication Date Title
US2034819A (en) Tire changer
US2356852A (en) Method and apparatus for making concrete pipe
US5028368A (en) Method of forming lined pipe
US2684517A (en) Concrete pipe casting apparatus
US2878545A (en) Collapsible cores for concrete pipe
US1810583A (en) Method and apparatus for making concrete pipe
DK144363B (en) CAST FORM FOR PREPARING CONCRETE OR SIMILAR WAY FORMABLE MATERIAL IN STANDING POSITION
US3345716A (en) Concrete pipe mold apparatus
US2823439A (en) Apparatus for making concrete culvert pipes
US4039642A (en) Method of making concrete pipe
JPS5825589B2 (en) Method for forming sand core part
US3114956A (en) Concrete pipe gasket groove forming apparatus
US2259975A (en) Tire-retreading apparatus
CA2653292C (en) Apparatus and method for protecting lined concrete pipe during the manufacturing process
US1836140A (en) Apparatus for forming concrete piles
US5139404A (en) Apparatus for making lined pipe
US3142882A (en) Mold for concrete structures
US2777163A (en) Tire retreading equipment
US5286440A (en) Method for the production of a symmerical oval concrete pipe
US2866250A (en) Single use fiber board mold for water meter barrels
US2160472A (en) Well casing extractor
US2723425A (en) Tire bead spreading device
US2814848A (en) Locking mechanism for a pipe mold structure
US2948044A (en) Pipe mold and ejector
US3188692A (en) Mold